Neil deGrasse Tyson, renowned astrophysicist and host of the popular television show “Cosmos,” is being investigated by National Geographic networks amid allegations of sexual misconduct.

The Web site Patheos reported on Thursday that Dr. Katelyn N. Allers, an associate physics professor at Bucknell, was “felt up” by Tyson after taking a photo with him at a 2009 party.

“After we had taken the picture, he noticed my tattoo and kind of grabbed me to look at it, and was really obsessed about whether I had Pluto on this tattoo or not . . . and then he looked for Pluto, and followed the tattoo into my dress,” Allers told the Web site.

The producers of “Cosmos” said in a statement: “The credo at the heart of ‘Cosmos’ is to follow the evidence wherever it leads. The producers of ‘Cosmos’ can do no less in this situation.”